Geometric sequence & series

A sequence of numbers u_1, u_2, …, u_n, … is given by the formula where n is a positive integer.
(a) Find the value of u_1, u_2 and u_3.
(b) Show that to 4 s.f.
(c) Proved that .
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A sequence of numbers u_1, u_2, …, u_n, … is given by the formula where n is a positive integer.
(a) Find the value of u_1, u_2 and u_3.
(b) Show that to 4 s.f.
(c) Proved that .
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